The tire tread compound is the most important compound in a tire that dictates wear, traction, and rolling resistance. It is a technical challenge to deliver excellent traction, low rolling resistance while providing good tread wear. The challenge lies in the trade-off between wet traction and rolling resistance/tread wear. Raising the compound Tg would provide good wet traction but, at the same time, increase the rolling resistance and tread wear. There is a need for tire treads that can provide wet traction without increasing the rolling resistance and tread wear.
Certain additives have been disclosed whose function is to adjust the wet traction or rolling resistance of tire treads but none have been successful at balancing both. For example, functionalized styrene butadiene rubber (SBR) is one proposed method to improve this trade-off by improving filler dispersion. Nanoprene™ from Lanxess, sub-micron to micron sized gels consisting of nanoscale organic particles with highly crosslinked core and hydroxylated surface, is another additive proposed to increase tire wet traction without affecting rolling resistance when the grade with certain Tg is chosen. What would be most useful is a tire tread additive that could balance both wet traction and rolling resistance.
Related references include U.S. 2014/088264; U.S. 2014/275433; U.S. 2012/0245293; U.S. 2012/0245300; PCT/US/2012/027677 filed Mar. 5, 2012; U.S. Ser. No. 61/704,611 filed on Sep. 23, 2012; U.S. Ser. No. 61/704,725 filed on Sep. 23, 2012; U.S. Ser. No. 61/866,702 filed Aug. 16, 2013; and U.S. Ser. No. 61/860,407, filed Jul. 31, 2013.